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1.
Authors analyse the 1684 bicycle accidents, observed in the county Vas in one year, compared with the international data. It is underlined that no sufficient attention is given to the bicycle accidents, reaching 6 per cents of all traumas, and the increase of which can be still expected, and to the prophylaxis of these accidents. Especially endangered were found the little children transported on bicycles, those aged 11-14 years and the drunken drivers. Prophylactic measures are suggested.  相似文献   
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In this paper, we present and validate a framework, based on deformable image registration, for automatic processing of serial three-dimensional CT images used in image-guided radiation therapy. A major assumption in deformable image registration has been that, if two images are being registered, every point of one image corresponds appropriately to some point in the other. For intra-treatment images of the prostate, however, this assumption is violated by the variable presence of bowel gas. The framework presented here explicitly extends previous deformable image registration algorithms to accommodate such regions in the image for which no correspondence exists. We show how to use our registration technique as a tool for organ segmentation, and present a statistical analysis of this segmentation method, validating it by comparison with multiple human raters. We also show how the deformable registration technique can be used to determine the dosimetric effect of a given plan in the presence of non-rigid tissue motion. In addition to dose accumulation, we describe a method for estimating the biological effects of tissue motion using a linear-quadratic model. This work is described in the context of a prostate treatment protocol, but it is of general applicability.  相似文献   
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Rhabdomyosarcoma (RMS) typically arises from skeletal muscle. Currently, RMS in patients with recurrent and metastatic disease have no successful treatment. The molecular pathogenesis of RMS varies based on cancer sub-types. Some embryonal RMS but not other sub-types are driven by sonic hedgehog (Shh) signaling pathway. However, Shh pathway inhibitors particularly smoothened inhibitors are not highly effective in animals. Here, we show that Shh pathway effectors GLI1 and/or GLI2 are over-expressed in the majority of RMS cells and that GANT-61, a specific GLI1/2 inhibitor dampens the proliferation of both embryonal and alveolar RMS cells-derived xenograft tumors thereby blocking their growth. As compared to vehicle-treated control, about 50% tumor growth inhibition occurs in mice receiving GANT-61 treatment. The proliferation inhibition was associated with slowing of cell cycle progression which was mediated by the reduced expression of cyclins D1/2/3 & E and the concomitant induction of p21. GANT-61 not only reduced expression of GLI1/2 in these RMS but also significantly diminished AKT/mTOR signaling. The therapeutic action of GANT-61 was significantly augmented when combined with chemotherapeutic agents employed for RMS therapy such as temsirolimus or vincristine. Finally, reduced expression of proteins driving epithelial mesenchymal transition (EMT) characterized the residual tumors.  相似文献   
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Background  Evidence-based medicine (EBM) is widely taught in residency, but evidence for effectiveness of EBM teaching on changing residents’ behavior is limited. Objective  To investigate the impact of an EBM curriculum on residents’ use of evidence-based resources in a simulated clinical experience. Design/Participants  Fifty medicine residents randomized to an EBM teaching or control group. Measurements  A validated test of EBM knowledge (Fresno test) was administered before and after intervention. Post intervention, residents twice completed a Web-based, multiple-choice instrument (15 items) comprised of clinical vignettes, first without then with access to electronic resources. Use of electronic resources was tracked using ProxyPlus software. Within group pre–post differences and between group post-test differences were examined. Results  There was more improvement in EBM knowledge (100-point scale) for the intervention group compared to the control group (mean score increase 22 vs. 12, p = 0.012). In the simulated clinical experience, the most commonly accessed resources were Ovid (71% of residents accessed) and InfoPOEMs (62%) for the EBM group and UptoDate (67%) and MDConsult (58%) for the control group. Residents in the EBM group were more likely to use evidence-based resources than the control group. Performance on clinical vignettes was similar between the groups both at baseline (p = 0.19) and with access to information resources (p = 0.89). Conclusions  EBM teaching improved EBM knowledge and increased use of evidence-based resources by residents, but did not improve performance on Web-based clinical vignettes. Future studies will need to examine impact of EBM teaching on clinical outcomes.  相似文献   
6.
OBJECT: The factors that determine the growth rates of vestibular schwannomas (VSs) in patients with neurofibromatosis Type 2 (NF2) are unknown. The authors undertook this study to determine if clinical factors or type of constitutional NF2 mutation were associated with VS growth rates in cases of NF2. METHODS: The authors reviewed serial gadolinium-enhanced magnetic resonance (MR) images of the head and full spine of 37 patients with sporadic NF2 who had been observed over periods ranging from 0.2 to 8 years (median 3.9 years) at a specialized referral clinic for NF2. A box model was used to calculate VS volumes so that tumor growth rates could be estimated. Temperature-gradient gel electrophoresis was used to screen for constitutional NF2 mutations. The VS growth rates tended to decrease with increasing patient age at onset of signs or symptoms (r2 = 0.23, p = 0.003) and at the time the baseline gadolinium-enhanced MR image was obtained (r2 = 0.38, p < 0.001). The authors did not find significant associations between VS growth rates and the number of non-VS cerebral or spinal tumors or different types of constitutional NF2 mutations. CONCLUSIONS: There is considerable variability in growth rates of VSs in patients with NF2, but they tend to be higher in patients who are younger at onset of signs or symptoms.  相似文献   
7.
This paper presents a general framework for analyzing structural and radiometric asymmetry in brain images. In a healthy brain, the left and right hemispheres are largely symmetric across the mid-sagittal plane. Brain tumors may belong to one or both of the following categories: mass-effect, in which the diseased tissue displaces healthy tissue; and infiltrating, in which healthy tissue has become diseased. Mass-effect brain tumors cause structural asymmetry by displacing healthy tissue, and may cause radiometric asymmetry in adjacent normal structures due to edema. Infiltrating tumors have a different radiometric response from healthy tissue. Thus, structural and radiometric asymmetries across the mid-sagittal plane in brain images provide important cues that tumors may be present. We have developed a framework that registers images with their reflections across the mid-sagittal plane. The registration process accounts for tissue displacement through large deformation image warping. Radiometric differences are taken into account through an additive intensity field. We present an efficient multi-scale algorithm for the joint estimation of structural and radiometric asymmetry. Results for nine MR images of patients with tumors and four normal control subjects are presented.  相似文献   
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Club drug use is becoming increasingly popular in the United States and has been associated with chronic psychiatric symptoms and neuropsychological abnormalities. Patterns of club drug use and characteristics of club drug users are not homogeneous. Thus, treatment-seeking marijuana-dependent individuals may have a differential pattern of club drug use. Baseline assessments collected from 55 individuals participating in a pharmacological treatment study for marijuana dependence were examined. Individuals completed a 16-item self-report questionnaire assessing club drugs used, frequency and patterns of use, problems associated with use, and reasons for use. Subjects were primarily male (87.3%) and Caucasian (81.8%), with a mean age of 32.1 (+/-9.1 years). As expected, a large number of individuals had used ecstasy (75%). However, LSD and methamphetamine use was also reported by many users (82.5% and 47.5% respectively), with many individuals reporting the use of more than one club drug. Notably, 31.6% of individuals reported tolerance to club drugs. These results emphasize the significant co-occurrence of club drug use in marijuana-dependent individuals. This appears to be the first study to report on club drug use in treatment-seeking marijuana-dependent individuals. Clinical implications and directions for future research are discussed.  相似文献   
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